String trimmers (also known as weed whackers, weed eaters and line trimmers) can help make landscapes neat and tidy by allowing you to edge and trim weeds, grass and overgrowth without having to use handheld shears and trimmers. But before you power up your machine for the first cut of the season, here are some tips on how to get it ready for action.

Gas String Trimmer Tune-Up Tips: Getting Your Machine Ready for Another Year of Work

1. Replace the spark plug and air filter.

With the engine off, remove the old spark plug and air filter. Put in a new spark plug and a fresh air filter to ensure your string trimmer runs more efficiently.  

2. Change the string, if needed.

When the string trimmer requires a new cutting line, you can either wind new line onto the existing reel or install a new spool. For either option, first remove the spool by taking off the cap. Then, clean the surface of the outer spool, inner spool and drive shaft with a clean rag. If you are replacing the spool, insert the new spool now. To rewind an existing spool with new string, measure about 50 feet of new line and insert each end of the line into the holes on the inner spool. Following the direction arrows indicated on the spool, wind the line tightly onto the reel following an even pattern.

When you are finished, insert the ends of the line into the notches. Now, you'll need to reinstall the spool by inserting the ends of the line into the holes in the outer spool and pulling the line through the holes.

Reattach the cap.  

3. Use the right string trimmer line.

It is important to note that different string trimmers require different types and sizes of line, so you must be careful to select the right line for your product. Using the wrong string can cause the line to break. If the line breaks, it may be launched at you, or at another person or object. Your operator's manual should indicate the type of line you need. If all else fails you can remove the spool and/or line and take it with you to ensure you purchase the right kind.

4. Choosing the right fuel: the problem with higher ethanol fuel blends.

Gas powered string trimmers are handy because they give you freedom to maneuver without a power cord. But using the wrong fuel in your string trimmer can damage or destroy the machine. Some gas stations now offer higher ethanol fuel blends, such as E15, E30 and E85. But using fuel blends above E10 in string trimmers, lawnmowers, leaf blowers and other small engine equipment will damage or destroy the products. Look before you pump, and select the right fuel for your string trimmer and other small engine equipment.

How to Use String Trimmers Safely

OK, you've tuned up your string trimmer now. You've cleaned it and changed the spark plug and air filter. You've put on a new line (if necessary) and ensured that you're using the right gas for it. You are ready to turn it on and tackle your next project. But not so fast. First, it's important to take a few steps to ensure you and the people, pets and property around you, stay safe. So here are some string trimmer safety precautions to remember:

1. Read the owner's manual.

Familiarize yourself with the operating instructions and safety measures for your particular unit.  

2. Dress properly.

Wear eye and ear protection, gloves, closed-toe shoes, and snug-fitting long-sleeved shirts and long pants.

3. Clear your work area.

Remove sticks, rocks, wires and other foreign objects that could be flung at you or others as you trim. Make sure there are no people or pets within 50 feet of the area in which you'll be working.

4. Stand strong.

Grip both of the machine's handles firmly, with each hand wrapping fully around the handles. Avoid uneven, sloped and slippery surfaces. Never work on a ladder and don't overreach.

5. Cut in the right direction.

Always cut away from yourself to keep dirt and debris from being propelled out of the string trimmer head toward you. For more maintenance and safety tips for all types of small engine equipment visit www.opei.org.

Editor's note: Want the freedom of going cordless without having to worry about unintentionally filling up with a higher ethanol fuel blend? Propane could be the answer. Read my review of a propane string trimmer. For more on staying safe in your landscaping endeavors, see my yard safety tips.